[ Upstream commit 313950c211 ]
It is not allowed to call kfree_skb() from hardware interrupt
context or with interrupts being disabled. All the SKBs have
been dequeued from the old queue, so it's safe to enqueue these
SKBs to a free queue, then free them after spin_unlock_irqrestore()
at once. Compile tested only.
Fixes: 5c99f04fec ("rtlwifi: rtl8723be: Update driver to match Realtek release of 06/28/14")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20221207141411.46098-4-yangyingliang@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 106031c1f4 ]
It is not allowed to call kfree_skb() from hardware interrupt
context or with interrupts being disabled. All the SKBs have
been dequeued from the old queue, so it's safe to enqueue these
SKBs to a free queue, then free them after spin_unlock_irqrestore()
at once. Compile tested only.
Fixes: 5c99f04fec ("rtlwifi: rtl8723be: Update driver to match Realtek release of 06/28/14")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20221207141411.46098-2-yangyingliang@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0ffcb2a68b ]
The default case for frame_contorl is invalid. We should always
assign addr3 of this frame properly.
Coverity error message:
if (ieee80211_has_a4(hdr.frame_control))
(19) Event uninit_use_in_call: Using uninitialized value "hdr".
Field "hdr.addr3" is uninitialized when calling "memcpy".
memcpy(skb_push(skb, sizeof(hdr)), &hdr, sizeof(hdr));
else
memcpy(skb_push(skb, sizeof(hdr) - 6), &hdr, sizeof(hdr) - 6);
Fixes: 0880d40871 ("mt76: connac: move mt76_connac2_reverse_frag0_hdr_trans in mt76-connac module")
Signed-off-by: Deren Wu <deren.wu@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit edb0406bda ]
In the expression "map[i].qid << 24" starts as u8, but is promoted to
"signed int", then sign-extended to type "unsigned long", which is not
intended. Cast to u32 to avoid the sign extension.
Fixes: 776ec4e77a ("mt76: mt7915: rework debugfs queue info")
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 59b27a7d47 ]
Check return value of mt7915_mcu_get_eeprom_free_block() first before
accessing free_block_num.
Fixes: bbc1d4154e ("mt76: mt7915: add default calibrated data support")
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit aec4cf2ea0 ]
SDIO may need addtional 511 bytes to align bus operation. If the tailroom
of this skb is not big enough, we would access invalid memory region.
For low level operation, increase skb size to keep valid memory access in
SDIO host.
Error message:
[69.951] BUG: KASAN: slab-out-of-bounds in sg_copy_buffer+0xe9/0x1a0
[69.951] Read of size 64 at addr ffff88811c9cf000 by task kworker/u16:7/451
[69.951] CPU: 4 PID: 451 Comm: kworker/u16:7 Tainted: G W OE 6.1.0-rc5 #1
[69.951] Workqueue: kvub300c vub300_cmndwork_thread [vub300]
[69.951] Call Trace:
[69.951] <TASK>
[69.952] dump_stack_lvl+0x49/0x63
[69.952] print_report+0x171/0x4a8
[69.952] kasan_report+0xb4/0x130
[69.952] kasan_check_range+0x149/0x1e0
[69.952] memcpy+0x24/0x70
[69.952] sg_copy_buffer+0xe9/0x1a0
[69.952] sg_copy_to_buffer+0x12/0x20
[69.952] __command_write_data.isra.0+0x23c/0xbf0 [vub300]
[69.952] vub300_cmndwork_thread+0x17f3/0x58b0 [vub300]
[69.952] process_one_work+0x7ee/0x1320
[69.952] worker_thread+0x53c/0x1240
[69.952] kthread+0x2b8/0x370
[69.952] ret_from_fork+0x1f/0x30
[69.952] </TASK>
[69.952] Allocated by task 854:
[69.952] kasan_save_stack+0x26/0x50
[69.952] kasan_set_track+0x25/0x30
[69.952] kasan_save_alloc_info+0x1b/0x30
[69.952] __kasan_kmalloc+0x87/0xa0
[69.952] __kmalloc_node_track_caller+0x63/0x150
[69.952] kmalloc_reserve+0x31/0xd0
[69.952] __alloc_skb+0xfc/0x2b0
[69.952] __mt76_mcu_msg_alloc+0xbf/0x230 [mt76]
[69.952] mt76_mcu_send_and_get_msg+0xab/0x110 [mt76]
[69.952] __mt76_mcu_send_firmware.cold+0x94/0x15d [mt76]
[69.952] mt76_connac_mcu_send_ram_firmware+0x415/0x54d [mt76_connac_lib]
[69.952] mt76_connac2_load_ram.cold+0x118/0x4bc [mt76_connac_lib]
[69.952] mt7921_run_firmware.cold+0x2e9/0x405 [mt7921_common]
[69.952] mt7921s_mcu_init+0x45/0x80 [mt7921s]
[69.953] mt7921_init_work+0xe1/0x2a0 [mt7921_common]
[69.953] process_one_work+0x7ee/0x1320
[69.953] worker_thread+0x53c/0x1240
[69.953] kthread+0x2b8/0x370
[69.953] ret_from_fork+0x1f/0x30
[69.953] The buggy address belongs to the object at ffff88811c9ce800
which belongs to the cache kmalloc-2k of size 2048
[69.953] The buggy address is located 0 bytes to the right of
2048-byte region [ffff88811c9ce800, ffff88811c9cf000)
[69.953] Memory state around the buggy address:
[69.953] ffff88811c9cef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[69.953] ffff88811c9cef80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[69.953] >ffff88811c9cf000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[69.953] ^
[69.953] ffff88811c9cf080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[69.953] ffff88811c9cf100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
Fixes: 764dee47e2 ("mt76: sdio: move common code in mt76_sdio module")
Suggested-by: Lorenzo Bianconi <lorenzo@kernel.org>
Tested-by: YN Chen <YN.Chen@mediatek.com>
Signed-off-by: Deren Wu <deren.wu@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3ce6a11598 ]
We support mixed merge for requests/bios with different fastfail
settings. When request fails, each time we only handle the portion
with same failfast setting, then bios with failfast can be failed
immediately, and bios without failfast can be retried.
The idea is pretty good, but the current implementation has several
defects:
1) initially RA bio doesn't set failfast, however bio merge code
doesn't consider this point, and just check its failfast setting for
deciding if mixed merge is required. Fix this issue by adding helper
of bio_failfast().
2) when merging bio to request front, if this request is mixed
merged, we have to sync request's faifast setting with 1st bio's
failfast. Fix it by calling blk_update_mixed_merge().
3) when merging bio to request back, if this request is mixed
merged, we have to mark the bio as failfast, because blk_update_request
simply updates request failfast with 1st bio's failfast. Fix
it by calling blk_update_mixed_merge().
Fixes one normal EXT4 READ IO failure issue, because it is observed
that the normal READ IO is merged with RA IO, and the mixed merged
request has different failfast setting with 1st bio's, so finally
the normal READ IO doesn't get retried.
Cc: Tejun Heo <tj@kernel.org>
Fixes: 80a761fd33 ("block: implement mixed merge of different failfast requests")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20230209125527.667004-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 2f1e07dda1 ]
Currently, uring_cmd with UBLK_IO_FETCH_REQ or
UBLK_IO_COMMIT_AND_FETCH_REQ is always checked whether
userspace server has provided IO buffer even flag
UBLK_F_NEED_GET_DATA is configured.
This is a excessive check. If UBLK_F_NEED_GET_DATA is
configured, FETCH_RQ doesn't need to provide IO buffer;
COMMIT_AND_FETCH_REQ also doesn't need to do that if
the IO type is not READ.
Check ub_cmd->addr together with ublk_need_get_data()
and IO type in ublk_ch_uring_cmd().
With this fix, userspace server doesn't need to preserve
buffers for every ublk_io when flag UBLK_F_NEED_GET_DATA
is configured, in order to save memory.
Signed-off-by: Liu Xiaodong <xiaodong.liu@intel.com>
Fixes: c86019ff75 ("ublk_drv: add support for UBLK_IO_NEED_GET_DATA")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20230210141356.112321-1-xiaodong.liu@intel.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 10de7b5429 ]
When support for ECDSA keys was added, constraints for data & signature
sizes were never updated. This makes it impossible to use such keys via
keyctl API from userspace.
Update constraint on max_data_size to 64 bytes in order to support
SHA512-based signatures. Also update the signature length constraints
per ECDSA signature encoding described in RFC 5480.
Fixes: 299f561a66 ("x509: Add support for parsing x509 certs with ECDSA keys")
Signed-off-by: Denis Kenzior <denkenz@gmail.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fd636b6a9b ]
Some of Nano series processors will lead GP when accessing
PMC fixed counter. Meanwhile, their hardware support for PMC
has not announced externally. So exclude Nano CPUs from ZXC
by checking stepping information. This is an unambiguous way
to differentiate between ZXC and Nano CPUs.
Following are Nano and ZXC FMS information:
Nano FMS: Family=6, Model=F, Stepping=[0-A][C-D]
ZXC FMS: Family=6, Model=F, Stepping=E-F OR
Family=6, Model=0x19, Stepping=0-3
Fixes: 3a4ac121c2 ("x86/perf: Add hardware performance events support for Zhaoxin CPU.")
Reported-by: Arjan <8vvbbqzo567a@nospam.xutrox.com>
Reported-by: Kevin Brace <kevinbrace@gmx.com>
Signed-off-by: silviazhao <silviazhao-oc@zhaoxin.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=212389
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 89e97eb8ce ]
The time order is incorrect when the TSC in a PEBS record is used.
$perf record -e cycles:upp dd if=/dev/zero of=/dev/null
count=10000
$ perf script --show-task-events
perf-exec 0 0.000000: PERF_RECORD_COMM: perf-exec:915/915
dd 915 106.479872: PERF_RECORD_COMM exec: dd:915/915
dd 915 106.483270: PERF_RECORD_EXIT(915:915):(914:914)
dd 915 106.512429: 1 cycles:upp:
ffffffff96c011b7 [unknown] ([unknown])
... ...
The perf time is from sched_clock_cpu(). The current PEBS code
unconditionally convert the TSC to native_sched_clock(). There is a
shift between the two clocks. If the TSC is stable, the shift is
consistent, __sched_clock_offset. If the TSC is unstable, the shift has
to be calculated at runtime.
This patch doesn't support the conversion when the TSC is unstable. The
TSC unstable case is a corner case and very unlikely to happen. If it
happens, the TSC in a PEBS record will be dropped and fall back to
perf_event_clock().
Fixes: 47a3aeb39e ("perf/x86/intel/pebs: Fix PEBS timestamps overwritten")
Reported-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/CAM9d7cgWDVAq8-11RbJ2uGfwkKD6fA-OMwOKDrNUrU_=8MgEjg@mail.gmail.com/
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7c4a5b89a0 ]
Commit 326587b840 ("sched: fix goto retry in pick_next_task_rt()")
removed any path which could make pick_next_rt_entity() return NULL.
However, BUG_ON(!rt_se) in _pick_next_task_rt() (the only caller of
pick_next_rt_entity()) still checks the error condition, which can
never happen, since list_entry() never returns NULL.
Remove the BUG_ON check, and instead emit a warning in the only
possible error condition here: the queue being empty which should
never happen.
Fixes: 326587b840 ("sched: fix goto retry in pick_next_task_rt()")
Signed-off-by: Pietro Borrello <borrello@diag.uniroma1.it>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20230128-list-entry-null-check-sched-v3-1-b1a71bd1ac6b@diag.uniroma1.it
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d44106883d ]
The memory region reserved by a previous commit (see fixes tag below)
overlaps with the SMEM and MPSS memory regions, causing error messages in
dmesg:
OF: reserved mem: OVERLAP DETECTED!
reserved@5000000 (0x0000000005000000--0x0000000007200000)
overlaps with smem_region@6a00000
(0x0000000006a00000--0x0000000006c00000)
OF: reserved mem: OVERLAP DETECTED!
reserved@6c00000 (0x0000000006c00000--0x0000000007200000)
overlaps with memory@7000000
(0x0000000007000000--0x000000000ca00000)
This patch resolves both of these by splitting the previously reserved
memory region into two sections either side of the SMEM region and by
cutting off the second memory region to 0x7000000.
Fixes: 22c7e1a0fa ("arm64: dts: msm8992-bullhead: add memory hole region")
Signed-off-by: Jamie Douglass <jamiemdouglass@gmail.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Tested-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230202054819.16079-1-jamiemdouglass@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 01542f651a ]
Commit 88022d7201 ("blk-mq: don't handle failure in .get_budget")
remove BLK_STS_RESOURCE return value and we only check if we can get
the budget from .get_budget() now.
Correct stale comment that ".get_budget() returns BLK_STS_NO_RESOURCE"
to ".get_budget() fails to get the budget".
Fixes: 88022d7201 ("blk-mq: don't handle failure in .get_budget")
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 47df9ce95c ]
Commit f906a6a0f4 ("blk-mq: improve tag waiting setup for non-shared
tags") mark restart for unshared tags for improvement. At that time,
tags is only shared betweens queues and we can check if tags is shared
by test BLK_MQ_F_TAG_SHARED.
Afterwards, commit 32bc15afed ("blk-mq: Facilitate a shared sbitmap per
tagset") enabled tags share betweens hctxs inside a queue. We only
mark restart for shared hctxs inside a queue and may cause io hung if
there is no tag currently allocated by hctxs going to be marked restart.
Wait on sbitmap_queue instead of mark restart for shared hctxs case to
fix this.
Fixes: 32bc15afed ("blk-mq: Facilitate a shared sbitmap per tagset")
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 98b99e9412 ]
For shared queues case, we will only wait on bitmap_tags if we fail to get
driver tag. However, rq could be from breserved_tags, then two problems
will occur:
1. io hung if no tag is currently allocated from bitmap_tags.
2. unnecessary wakeup when tag is freed to bitmap_tags while no tag is
freed to breserved_tags.
Wait on the bitmap which rq from to fix this.
Fixes: f906a6a0f4 ("blk-mq: improve tag waiting setup for non-shared tags")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c31e76bcc3 ]
Commit 97889f9ac2 ("blk-mq: remove synchronize_rcu() from
blk_mq_del_queue_tag_set()") remove handle of TAG_SHARED in restart,
then shared_hctx_restart counted for how many hardware queues are marked
for restart is removed too.
Remove the stale comment that we still count hardware queues need restart.
Fixes: 97889f9ac2 ("blk-mq: remove synchronize_rcu() from blk_mq_del_queue_tag_set()")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6ee858a3d3 ]
Commit 1f5bd336b9 ("blk-mq: add blk_mq_alloc_request_hctx") add
blk_mq_alloc_request_hctx to send commands to a specific queue. If
BLK_MQ_REQ_NOWAIT is not set in tag allocation, we may change to different
hctx after sleep and get tag from unexpected hctx. So BLK_MQ_REQ_NOWAIT
must be set in flags for blk_mq_alloc_request_hctx.
After commit 600c3b0cea ("blk-mq: open code __blk_mq_alloc_request in
blk_mq_alloc_request_hctx"), blk_mq_alloc_request_hctx return -EINVAL
if both BLK_MQ_REQ_NOWAIT and BLK_MQ_REQ_RESERVED are not set instead of
if BLK_MQ_REQ_NOWAIT is not set. So if BLK_MQ_REQ_NOWAIT is not set and
BLK_MQ_REQ_RESERVED is set, blk_mq_alloc_request_hctx could alloc tag
from unexpected hctx. I guess what we need here is that return -EINVAL
if either BLK_MQ_REQ_NOWAIT or BLK_MQ_REQ_RESERVED is not set.
Currently both BLK_MQ_REQ_NOWAIT and BLK_MQ_REQ_RESERVED will be set if
specific hctx is needed in nvme_auth_submit, nvmf_connect_io_queue
and nvmf_connect_admin_queue. Fix the potential BLK_MQ_REQ_NOWAIT missed
case in future.
Fixes: 600c3b0cea ("blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 366384e495 ]
The STM32MP13x Device Part Number (also named RPN in reference manual)
only uses the first 12 bits in OTP4, all the other bit are reserved and
they can be different of zero; they must be masked in NVMEM result, so
the number of bits must be defined in the nvmem cell description.
Fixes: 1da8779c00 ("ARM: dts: stm32: add STM32MP13 SoCs support")
Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b5fcf7871a ]
Commit 180dccb0db ("blk-mq: fix tag_get wait task can't be awakened")
mentioned that in case of shared tags, there could be just one real
active hctx(queue) because of lazy detection of tag idle. Then driver tag
allocation may wait forever on this real active hctx(queue) if wake_batch
is > hctx_max_depth where hctx_max_depth is available tags depth for the
actve hctx(queue). However, the condition wake_batch > hctx_max_depth is
not strong enough to avoid IO hung as the sbitmap_queue_wake_up will only
wake up one wait queue for each wake_batch even though there is only one
waiter in the woken wait queue. After this, there is only one tag to free
and wake_batch may not be reached anymore. Commit 180dccb0db ("blk-mq:
fix tag_get wait task can't be awakened") methioned that driver tag
allocation may wait forever. Actually, the inactive hctx(queue) will be
truely idle after at most 30 seconds and will call blk_mq_tag_wakeup_all
to wake one waiter per wait queue to break the hung. But IO hung for 30
seconds is also not acceptable. Set batch size to small enough that depth
of the shared hctx(queue) is enough to wake up all of the queues like
sbq_calc_wake_batch do to fix this potential IO hung.
Although hctx_max_depth will be clamped to at least 4 while wake_batch
recalculation does not do the clamp, the wake_batch will be always
recalculated to 1 when hctx_max_depth <= 4.
Fixes: 180dccb0db ("blk-mq: fix tag_get wait task can't be awakened")
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Link: https://lore.kernel.org/r/20230116205059.3821738-6-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4f8126bb23 ]
sbitmap suffers from code complexity, as demonstrated by recent fixes,
and eventual lost wake ups on nested I/O completion. The later happens,
from what I understand, due to the non-atomic nature of the updates to
wait_cnt, which needs to be subtracted and eventually reset when equal
to zero. This two step process can eventually miss an update when a
nested completion happens to interrupt the CPU in between the wait_cnt
updates. This is very hard to fix, as shown by the recent changes to
this code.
The code complexity arises mostly from the corner cases to avoid missed
wakes in this scenario. In addition, the handling of wake_batch
recalculation plus the synchronization with sbq_queue_wake_up is
non-trivial.
This patchset implements the idea originally proposed by Jan [1], which
removes the need for the two-step updates of wait_cnt. This is done by
tracking the number of completions and wakeups in always increasing,
per-bitmap counters. Instead of having to reset the wait_cnt when it
reaches zero, we simply keep counting, and attempt to wake up N threads
in a single wait queue whenever there is enough space for a batch.
Waking up less than batch_wake shouldn't be a problem, because we
haven't changed the conditions for wake up, and the existing batch
calculation guarantees at least enough remaining completions to wake up
a batch for each queue at any time.
Performance-wise, one should expect very similar performance to the
original algorithm for the case where there is no queueing. In both the
old algorithm and this implementation, the first thing is to check
ws_active, which bails out if there is no queueing to be managed. In the
new code, we took care to avoid accounting completions and wakeups when
there is no queueing, to not pay the cost of atomic operations
unnecessarily, since it doesn't skew the numbers.
For more interesting cases, where there is queueing, we need to take
into account the cross-communication of the atomic operations. I've
been benchmarking by running parallel fio jobs against a single hctx
nullb in different hardware queue depth scenarios, and verifying both
IOPS and queueing.
Each experiment was repeated 5 times on a 20-CPU box, with 20 parallel
jobs. fio was issuing fixed-size randwrites with qd=64 against nullb,
varying only the hardware queue length per test.
queue size 2 4 8 16 32 64
6.1-rc2 1681.1K (1.6K) 2633.0K (12.7K) 6940.8K (16.3K) 8172.3K (617.5K) 8391.7K (367.1K) 8606.1K (351.2K)
patched 1721.8K (15.1K) 3016.7K (3.8K) 7543.0K (89.4K) 8132.5K (303.4K) 8324.2K (230.6K) 8401.8K (284.7K)
The following is a similar experiment, ran against a nullb with a single
bitmap shared by 20 hctx spread across 2 NUMA nodes. This has 40
parallel fio jobs operating on the same device
queue size 2 4 8 16 32 64
6.1-rc2 1081.0K (2.3K) 957.2K (1.5K) 1699.1K (5.7K) 6178.2K (124.6K) 12227.9K (37.7K) 13286.6K (92.9K)
patched 1081.8K (2.8K) 1316.5K (5.4K) 2364.4K (1.8K) 6151.4K (20.0K) 11893.6K (17.5K) 12385.6K (18.4K)
It has also survived blktests and a 12h-stress run against nullb. I also
ran the code against nvme and a scsi SSD, and I didn't observe
performance regression in those. If there are other tests you think I
should run, please let me know and I will follow up with results.
[1] https://lore.kernel.org/all/aef9de29-e9f5-259a-f8be-12d1b734e72@google.com/
Cc: Hugh Dickins <hughd@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Liu Song <liusong@linux.alibaba.com>
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/20221105231055.25953-1-krisman@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: b5fcf7871a ("sbitmap: correct wake_batch recalculation to avoid potential IO hung")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 903e86f3a6 ]
Commit fbb564a557 ("lib/sbitmap: Fix invalid loop in
__sbitmap_queue_get_batch()") mentioned that "Checking free bits when
setting the target bits. Otherwise, it may reuse the busying bits."
This commit add check to make sure all masked bits in word before
cmpxchg is zero. Then the existing check after cmpxchg to check any
zero bit is existing in masked bits in word is redundant.
Actually, old value of word before cmpxchg is stored in val and we
will filter out busy bits in val by "(get_mask & ~val)" after cmpxchg.
So we will not reuse busy bits methioned in commit fbb564a557
("lib/sbitmap: Fix invalid loop in __sbitmap_queue_get_batch()"). Revert
new-added check to remove redundant check.
Fixes: fbb564a557 ("lib/sbitmap: Fix invalid loop in __sbitmap_queue_get_batch()")
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Link: https://lore.kernel.org/r/20230116205059.3821738-3-shikemeng@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>